The following list highlights sleep-disrupting habits that can sabotage your slumber. Take a look at these offenders—and avoid them—to optimize your sleep!

Sleep Mistake #1: Eating too close to bedtime. Late-night meals and snacks prevent your body from cooling down during sleep and raise your insulin level. As a result, less cell-boosting melatonin and growth hormone are released while you snooze.

Fix It: Stop eating 3 hours before bed.

Sleep Mistake #2: Sleeping with light exposure or too close to your digital alarm clock. Even a small amount of light interferes with the release of melatonin and, subsequently, the release of growth hormone. Cortisol also remains abnormally high when you are exposed to light.

You should also be away of electromagnetic fields (EMFs) that are emitted from electrical devices and digital alarm clocks in your bedroom. These can disrupt the pineal gland and the production of melatonin and serotonin. Research has also linked EMFs to increased risk of cancer.

Fix It: Sleep in pitch dark and keep electrical equipment at least 3 feet away, if you must use these items. Turn the light display away from your line of sight.

Sleep Mistake #3: Drinking too much liquid before bed. Drinking before bedtime can definitely increase your need for late-night trips to the toilet. Waking to go to the bathroom interrupts your natural sleep patterns. If you turn the light on when you go, you also run the risk of suppressing melatonin production.

Fix It: Stop drinking two hours before bedtime and use a red night light in the bathroom, if a night light is needed.

Sleep Mistake #4: Exercising late at night. Regular exercise can certainly help you sleep better, as long as you do it early enough in the day. A late-night workout, especially a cardio session, raises body temperature significantly, preventing the release of melatonin. It can also interfere with your ability to fall asleep, since it usually increases noradrenaline, dopamine, and cortisol, which stimulate brain activity.

Fix It: Avoid cardiovascular exercise in the 3-hour period before bed.

Sleep Mistake #5: Too much TV or computer use before bed. Many of us enjoy watching favorite TV shows, catching up on emails, or surfing the Net in the evenings, but too much time in front of either screen close to bedtime can interfere with a good night's rest. Both these activities increase the stimulating hormones noradrenaline and dopamine, which can hamper your ability to fall asleep.

Fix It: Take time to "power down" and focus on mind-calming activities like meditation, reading, or journaling. These habits make your serotonin dominant and improve your sleep.

Sleep Mistake #6: Keeping your bedroom too warm. Plenty of people like to feel cozy at bedtime, but a sleep environment that's too warm can prevent the natural cooling that should take place in your body while you sleep.

Without this cool-down process, melatonin and growth-hormone release is disrupted, which means you won't burn fat while you sleep or benefit from nighttime repair of your bones, skin, and muscles.

Sleep Mistake #7: Sleeping in tight-fitting clothes. Besides feeling comfy, your favorite PJs can actually help you sleep better, but not if they're too tight. Wearing tight-fitting clothing at bedtime—even a bra or underwear—appears to raise your body temperature and has been proven to reduce secretion of melatonin and growth hormone.

Fix It: Sleep in the nude and avoid excessive, heavy blankets. If you prefer to wear something to bed, make sure it's light and loose fitting.

Sleep Mistake #8: Failure to open the blinds or go outside in the morning. Remember, melatonin is supposed to be lowest first thing in the morning. If you remain in darkness, your body will not get the signal that the time has come to get up and go. High melatonin during the day leaves you feeling fatigued and unable to wake up properly. It may also lower serotonin, leading to depression, anxiety, and cravings.

Fix It: Let the light in as soon as you wake.

Sleep Mistake #9: Not getting the right amount of sleep. The American Cancer Association found higher incidences of cancer in individuals who consistently slept six hours or less or more than nine hours nightly. New research recently reported that people who regularly sleep 7½ hours per night live longer.

Most sleep experts agree that seven to eight hours a night is optimal. However, some people may require more or less sleep than others. If you wake without an alarm in the morning and feel refreshed when you get up, you're likely getting the right amount of sleep for you.

When your sleep is insufficient, your cortisol and hunger hormones both surge, causing a corresponding increase in insulin. You also experience decreases in leptin, melatonin, growth hormone, testosterone, and serotonin, all of which lead to weight gain.

Fix It: Aim for 7½ to nine hours nightly.

Sleep Mistake #10: Going to bed too late. More than half the respondents to the 2005 National Sleep Survey reported they are morning people with higher energy earlier in the day, while 41 percent considered themselves night owls. Evening people were more likely than morning people to experience symptoms of insomnia and sleep apnea, enjoy less sleep than they felt they needed, and take longer to fall asleep.

Staying awake until the wee hours causes hormonal imbalance because it increases cortisol, decreases leptin, and depletes growth hormone. It can also cause us to eat more, and it messes with our metabolism. Cortisol naturally begins to increase during the second half of your sleep—a small boost at 2 a.m., another at 4 a.m., and the peak at around 6 a.m. If you're just getting to bed immediately beforehand, you're missing out on your most restful period of sleep.